03/25/2014 10:52 EDT | Updated 05/25/2014 05:59 EDT

Ukraine crisis: G7 leaders threaten to 'intensify' sanctions against Russia

International political leaders continued their condemnation of what they're calling Russia’s aggression toward Ukraine Tuesday at a meeting in The Hague.

Many world leaders are in the Netherlands for the Nuclear Security Summit, but side discussions about Ukraine have overshadowed the summit’s regular agenda. On Wednesday, G7 leaders issued a declaration reiterating their support for Ukraine’s new government and calling Russia’s annexation of Crimea illegal.  

The leaders “reaffirm our support for Ukraine's sovereignty, territorial integrity and independence,” the declaration read.

The G7 countries — Canada, France, Germany, Italy, Japan, the U.K. and U.S. — called on Russia to de-escalate tensions with Ukraine, and begin talks with the interim government. There is still room for a diplomatic solution, the G7 countries said.

If Russia doesn’t act, G7 leaders have vowed to “intensify” sanctions, including what they called "co-ordinated sectoral sanctions" designed to have a “significant impact” on the Russian economy.

The G7 did praise Russia for its decision to allow observers from the Organization for Security and Co-operation in Europe (OSCE) into Ukraine.

Representatives from Ukraine, meanwhile, worked on a deal with the International Monetary Fund to provide a $15-20-billion relief package.